To give light ... - See the notes at Matthew 4:16.
To guide our feet ... - The figure in these verses is taken from travelers, who, being overtaken by night, know not what to do, and who wait patiently for the morning light, that they may know which way to go. So man wandered. So he became benighted. So he sat in the shadow of death. So he knew not which way to go until the Sun of righteousness arose, and then the light shone brightly on his way, and the road was open to the promised land of rest - to heaven.
This song of Zechariah is exceedingly beautiful. It expresses with elegance the great points of the plan of redemption, and the mercy of God in providing that plan. That mercy is “great.” It is worthy of praise - of our highest, loftiest songs of thanksgiving; for we were in the shadow of death - sinful, wretched, wandering - and the light arose, the gospel came, and people may rejoice in hope of eternal life.